Comment by mishoo

In SLip: https://lisperator.net/s/slip/

    SL-USER> (time (loop for i below (expt 10 8) count t))
    Evaluation time: 19376ms
    100000000

    SL-USER> (time (loop for i below 1000000 count t))
    Evaluation time: 272ms
    1000000

    SL-USER> (defun fib (n) (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
    #'FIB
    SL-USER> (time (fib 32))
    Evaluation time: 1601ms
    2178309

These timings are in Firefox; Chromium is almost 2x faster. Also, it doesn't completely freeze the browser in the mean time (we have green threads).

I used to think it's quite slow, but somehow it's much faster than any other posted here. The only Lisp in browser I know to beat SLip (by a large margin) is JSCL, which compiles to JS.